Furnace



Aug. 12, 1924. 1,504,835

J. T. M TARNAHAN FURNACE Filed 21. 1921 3 Sheets-Sheet l mam Z27 Aug. 12 192.4, 1,504,835

J T. M TARNAHAN FURNACE File'd Dec. 21. 1921 3 Sheets-Sheet 2 ll llll I I I I I I I 77%M 4%7WM Aug. 12 1924. I r 1,504,835

v J. T. M TARNAHAN FURNACE Filed Dec. 21. 1921 3 Sheets-Sheet 5 oil flame into 'a large 0 Patented Au 12, 1924.

UNITED STATES 1,5 ,8 5 PATENT OFF-ICE.

( 101m 1 nc'ra'nnam, or nos'rou, noun-r,

roaa'non, mum,

IASSAOHUSEI'I'S, AfiSIGHOB 'I'O RALPE H. CA- TBUSTEE I]! BANKRUPTCY O I O! BOSTON, nssacnusms, A CORPORATION OF ASSA- F xc'rmam FUH: OIL BURNING COB- FURNACE.

Application fled MIN! 81, 1831. Serial Io. 583,857.

To all whom it may comm:

Be it known that I, JOHN T. Mo'lma- HAN, a citizen of the United States, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented an Improvement in Furnaces, of which the fol-. lowing description,

in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts. 1

The invention to be hereinafter described relates to furnaces for boilers and other uses, and more particularly to fuel oil furnaces. p

In furnaces of this type, a burner or burners may be employed for projecting atomized fuel oil into the furnace, suitable means being provided. for regulating the flow of -fue accordingto whether high or low heating effect is desired.

It has been customary to inject the fuel n combustion chamber similar to that o a coal burning furnace, but with the grate removed. It has been found that when the regulator reduces the fuel supply for low heating effect, the

flame issuing from the burner frequently is puffed out or extin ished. This was due to lack of suflicientfi high temperature in the furnace, and to lack of proper protection for the flame from eddies and. drafts in.the furnace. In some instances on reduction of the fuel supply, the flame was not reduced to such an extent as to cause the same to be extinguished, but it was found that the flame would lose its proper direction for proper heating effect.

As a result of the aforesaid conditions, unconsumed particles of oil would fly \ofi, strike the heating surfaces of the boiler. and develop obnoxious gases which would escape through the stack and fill the nei hborhood with a bad odor. This caused gequent complaints from persons livin in the vicinity and frommunicipal hea th departments. Also, the unconsumed particles would deposit soot on the heating surfaces and other arts in the interior of the boiler. These con itions materially reduced the cf -ficiency of the combustion, and required an excessive amount of air to support the combustion, which, as is well known, is one of the principal factors in causing ineflicient combustion of fuel oil.

Sometimes if the temperature within the furnace was not too low, the flame would rel' ht, therebycausing a sharp explosion liab e to frighten the caretaker of the boiler, and the people in the building in which the boiler isinstalled.

One of the purposes of the resent invention, therefore, 1s to .provi e a furnace which will overcome the aforesaid objectionable conditions, that is, a furnace which will store upor retain suflicient heat to prevent the fire from bein snuffed out or extinguished when regu ation is used for low heating effect; a furnace thatwill protect a low flame from eddies and drafts, and thus prevent the flame from being puffed out or extinguished or from losing its proper direction; a furnace which will store up or retain suflicient heat to burn all of the oil projected from the burner, and thereby materially reduce de osit of soot on the heating surfaces, an prevent malodorous gases fromescape through the stack into the neighborhood; and a furnace which will prevent explosions therein. In other words, the purpose is to provide a furnace which will result in maximum efliciency of combustion of the fuel oil, reduce the fuel oil consumed, and increase the efliciency of the boiler in which the furnace is used.

In carrying these features of the invention into practical effect, in the present instance, a furnace is provided having a combustion chamber so formed and arranged in relation to the burner, that the walls of the chamber protect the flame, when regu- ,lated for low heating effect, from eddies and drafts in the furnace. The walls and arch or roof of the chamber are highly heated by the flame issuing from the burner, so that, the heat stored in the walls, radiates back into q the chamber and contributes to eflicient combustion of the fuel oil when the flame is regulated for both low and high heatingeifect. The combustion chamber is of substantial length, and the flame must pass therethrough before coming in contact with the water tubes or other surfaces of the boiler to be heated. As a consequence,

the flame path is desirably lengthened, and

skilled labor.

labor and expense of construction have been objectionable, due to the importance of constructin the chamber of proper form and size} sually the ordinary mason cannot be relied upon to construct the chamber properly, and therefore, supervision of his work has been required.

Another purpose of the present invention, therefore, is to provide a combustion chamber which may be constructed of specially formed ceramic blocks which practically determine the form and size of the combustion chamber. These blocks may be formed for interlocking relation with uniting elements which will securely hold the blocks in assembled relation. The construction is such that'the form and size of the blocks may be standardized, thereby enabling them to e quickly and easily assembled properly to form the combustion chamber, and without requiring the services of expensive,

With the aforesaid and other purposes in view, the character of the invention may be best understood by reference to the following description of one good form of the invention shown in the accompanying drawin wherein:

ig. 1 is a front elevation of a boiler equipped with a furnace embodying the invention;

Fig. 2 on a enlarged scale is a perspective View of portions of the blocks of the walls of the furnace, illustrating the means for connecting the blocks;

Fig. 3 is a vertical longitudinal section taken on line 3-3 of Fig. 1; and

Fig. 4 on an enlarged scale is a vertical transverse section through the furnace.

The furnace is suitable for a variety of boilers, such, for example, ashorizontal, vertical, water tube, steam tube, Dutch oven, front or rear fired, and other types of boilers, but for purposes of illustration, in the present instance, the furnace is shown in a sectional water tube boiler. V p This boiler comprisesa cast iron base 1 formed of plates '3having strengthening flanges 5.

Mounted on opposite sides of the base .are hollow sections-7 which extend upward and have 1y inward the boiler.

Above the top portions of the hollow sections is a. steam drum 11 connected to the portions 9 extending horizontalto form the top orcrown of hollow sections by nipples 13 which may be disposed in staggered relation. Adjacent the lower endsof the hollow sections are side drums 15 connected to the hollow sections by nipples 17. One of the side drums may beiconnected by a pipe 19 with the steam drum, said pipe being provided with the usual water gage 21 and valves 23.

Mounted on the base is a hollow from wall 25 connected by a nipple 27 with the steam drum, said wall being provided with doors 29 and 31, furnishing access to water tubes and other parts to be described, within the boiler.

At the rear of the boiler is ahollow wall 33 connected to the steam drum by a nipple 35. This wall is provided with an opening 37 communicating with a chamber 39, communicating in turn with a pi e 41 adapted for connection with the chimne or stack, said pipe being provided wit the usual damper 43.

Rows of water tubes 45, 47 and 49, may be threaded into the hollow Wall sections and project horizontally inward toward one another beneath the top of the boiler. The tubes 45 are in spaced relation to allow the gases of combustion to envelope and pass upward between the same. The tubes 47 of the intermediate row are also in spaced relation, but these tubes are connected by wings 51, with the exception of the tubes 47 which are spaced to provide passages 53, allowing the gases of combustion to pass .upward to the top row of tubes '49, which are i11 spaced relation to allow the gases of combustion to envelope and pass between them. The construction is such that the gases of combustion coming from the combustion. chamber to be described, are caused to pass along the lower row of tubes 45 toward the front of the boiler, thence upward through the spaces 53 between the tubes 47 of the intermediate row of tubes, and. thence upward be tween the upper row of tubes 49. The gases then flow rearward beneath the top portions 9 of the hollow sections, and thence into the chamber 39 and the pipe 41 leading to the chimney stack.

The boiler thus far described may be of usual well known construction in its principal features, and therefore, it is unnecessary to describe the same further in detail herein.

One of the end. walls ,of the boiler, in the present instance the front wall, may be provided with a door 55 having an aperture receiving a fuel oil burner 57 of well known construction, said burner, in the present instance, being provided with a collar 59 secured to the door by bolts 61. The fuel oil and atomizing fluid may be conducted from sources of supply to the burner by usual means unnecessary to show and describeherein.

As stated, one of the purposes of the present invention, is to provide a furnace constructed and arranged to promote efficient combustion of the fuel oil. This furnace is formed to provide a combustion chamber 63 of substantial length, and having solid, thick, heat storing walls and a crown or arch which are sufficiently near to the flame issuing from the burner to be highly heated thereby. The heat stored in the walls and arch will radiate back into the combustion chamber and contribute to eflicient combustion of the fuel.

This furnace may be constructed of suitable materials, but in the present instance, it

is formed of ceramic refractory blocks which may be of a form and size substantially to determine their assemblage and the shape of the combustion chamber.

To accomplish this, in the resent instance, a series of floor blocks is provided,

preferably of alength I one side of the the side blocks are arch blocks 71. In the present instance. three of these arch blocks are provided, but it will be understood that the number thereof ma be varied according to the length of com ustion chamber required.

In alinement with and rojectin rearward from the side blocks 6 are ad 'tional side blocks 7 3 projecting to the rear wall 0 the boiler and rising somewhat above the top of the combustion chamber.

Extendin between the side blocks 73 is a rear or ba e wall comprising a lower block 75 having a curved deflecting surface 77, intermediate blocks 79, and an upper block 81 having a curved deflecting 83 extending toward the combustion chamber. Mounted on the upper block 81 is a top block 85.

At the front of the boiler is a wall comprising a series of blocks 87, which may be supported by the front floor block, and constitute the front wall. of the combustionchamber. Certainof these front wall blocks may have an aperture 91 to receive the inner end of the burner, said aperture being lined by a collar 93.

Whenthe burner is in active firing position, the door 55 is closed and the burner projects inward somewhat beyond the collar 93. When the burner is inactive, the door isswung open, thereby moving the burner out ward where it will be protected from residual heat in the combugion chamber.

Air for supporting combustion of the'fuel may be admitted into the'combustion chamber through an elongated Er: 95 formed in the lowest block of the t wallof the chamber and in the front base plate, said port being provided with as hinged damper 95' which may be manually regulated or automatically regulated by means unneces sarv todisclose herein.

tion. is to provide means for connecting the their mouths.

grooves of the blocks are locking elements, In

desired to facilitate their f o 11 end of the chamber.

blocks of the furnace to hold the same securely in asembled relation. To accomplish this, in the present instance, the blocks are provided with opposed grooves 97 which may flare inwardl .or have ases wider than ounted in the opposed the present instance, in the form of bars 99 which desirably may be of I-bar cross section having heads 101 for interlocking engagement with the grooves 97.

n bling the blocks, they may be placed in proper superposed relation with the ves 0 adjacent blocks in opposed relation, and then the interlocking bars may be and longitudinally into the grooves,

.thereby securely to hold the blocks relative movement. locking g g ve Preferably the interbars do not have a close fit with the but are somewhat smaller than said to permit expansion and contraction of bars under temperature changes, with i displacement or breaka e blocks may be num red if assembly.

at one end of the out causin blocks.

The burner is located .combustion chamber, and the flame passes from the opposite The disposition o the chamber with relation to the water tubes or surfaces ma vary in different of boilers, but the c amber should be so 0- cated that the gases of combustion will be delivered by the open end of the chamber at a point where the gases will start on a flame whichwill bring them in contact with all of "thetubes or other heating surfaces.

therethrough and issues In the present instance, the gases are de-' livered at the rear end of the furnace to the rear tubes of the lowest row of water tubes. They pass thence forwardly surrounding the lowest row of tubes and in contact with the a under surfaces of the intermediate row of tubes. Then they pass upward through the spaces 53 and flow rearward about the top row of tubes toward the stack opening.

By my invention a furnace 18 provided which desirably cooperates with the burner to store up heat in the walls and arch or roof of the combustion chamber. This heat is radiated back into the chamber to maintain a temperature therein sufliciently high to insure combustion of the oil when regulated for low heat eflect. Deposit of soot on the heating surfaces is malodorous from the stack, and explosions in t furnace are prevented; The

reduced, and escape of ofthe combustion chamber so. surrounds and pm tools the flame from eddies and drafts in the furnace, that the flame is always properly directed without localization of the heat therefrom. Also, it is unnece$ary to introduce excess air into the combustion chamber, As stated, another purposeofthe vinven-' but, on the contrary, a

cient combustion of the fuel oil. A further advantage is in the and thereby prevent rapid contraction there- 4 wall having an upper deflecting portion exofwhich might cause lnjury thereto.

The specially formed ceramic blocks and their uniting elements enable the furnace to be quickly, easily and properly constructed by cheap labor in minimum time and with minlmum expense. It will be understood, however, that it is not indispensable that the furnace shall beconstructed of ceramic blocks, but, on the contrary, it may be desirably constructed of metal or other material if desired.

It will be understood that the invention is not limited to the specific embodiment shown, and that various deviations may be made therefrom without departing from the spirit and scope of the appended claims.

What is claimed is 1. In a furnace, a combustion chamber of substantial length comprising side walls, a crown, an end wall, and an upright baflle tending a sli ht distance toward the crown, said baflle wall being spaced from the crown to leave an outlet, and said side walls having upstanding portions projecting above the crown between the ba-flie and the end of the crown; and a fuel oil burner entered through the end'wall for projecting its flame into the combustion chamber toward the baflle wall, that the baflle wall and the upstanding portions of the side walls may direct the gases of combustion upward; the side walls and crown of said combustion chamber being of solid, thick, heat storing ceramic material and closely related in respect to the burner so as to become highly heated by the flame from the burner and store up heat to be ra-- diated back into the combustion chamber and promote combustion of the fuel oil. v

2. In a furnace, a combustion chamberof substantial length comprisin sidewalls, a crown and end walls, one o the end walls being spaced a substantial distance from one end of the crown to leave an outlet, said side walls and crown being formed of solid, thick blocks of ceramic material specially formed to determine the shape and size of the combustion chamber, certain of said side wall blocks being formed to provide .abutments for supportlng the crown blocks, the side wall and crown blocks havin opposed horizontal grooves therein, metal ic uniting elements in said grooves, said elements and grooves being formed for interlockin engagement, thereby to secure the blocks in assembled relation; and a fuel oil burner en,- tered through one of the end walls for projecting its flame through the combustion chamber toward'the opposite end wall, that the ases of combustion may be deflected by the datter up through the outlet; theside walls and crown of the combustion chamber being closely related in res t to the burner so as to be highly heated y the flame and store up heat to be radiated back into the combustion chamber and promote combustion of the fuel oil.

In testimony whereof, I have signed my name to this s ification.

J HN T. McTARNAHAN. 

